lxiv REPORT 1860. 



comet of Encke, which performs its revolution in a period of a little more than 

 three years, was observed at each return, it disclosed the important and unex- 

 pected fact, that its motion was continually accelerated. At each successive 

 approach to the Sun it arrives at its perihelion sooner and sooner; and there 

 is no way of accounting for this so satisfactory as that of supposing that the 

 space, in which the planetary and cometary motions are performed, is every- 

 where pervaded by a very rarefied atmosphere or ether, so thin as to exercise 

 no perceptible effect on the movements of massive solid bodies like the planets, 

 but substantial enough to exert a very important influence on more attenuated 

 substances moving with great velocity. The effect of the resistance of the 

 ether is to retard the tangential motion, and allow the attractive force of 

 gravity to draw the body nearer to the Sun, by which the dimensions of the 

 orbit are continually contracted and the velocity in it augmented. The final 

 result will be that after the lapse of ages this comet will fall into the Sun; 

 this body, a mere hazy cloud, continually flickering as it were like a celestial 

 moth round the great luminary, is at some distant period destined to be mer- 

 cilessly consumed. Now the discovery of this ether is deeply interesting as 

 bearing on other important physical questions, such as the undulatory theory 

 of light; and the probability of the future absorption of comets by the Sun 

 is important as connected with a very interesting speculation by Professor 

 William Thomson, who has suggested that the heat and light of the Sun may 

 be from time to time replenished by the falling in and absorption of count- 

 less meteors which circulate round him; and here we have a cause revealed 

 which may accelerate or produce such an event. 



In the progress of science it often happens that a particular class of obser- 

 vations, all at once, and owing to some peculiar circumstance, attracts very 

 general attention and becomes deeply interesting. This has been the case 

 within the last few years in reference to observations of the Sun's disc, which 

 were at one time made by very few individuals, and were indeed very much 

 neglected both by professional and amateur Astronomers. During this sea- 

 son of comparative neglect, there were not, however, wanting some enthusiastic 

 individuals, who were in silence and seclusion obtaining data of great import- 

 ance. 



On the 1st of September last, at ll h 18 m a.m., a distinguished Astronomer, 



Mr. Carrington, had directed his telescope to the Sun, and was engaged in 

 observing his spots, when suddenly two intensely luminous bodies burst into 

 view on its surface. They moved side by side through a space of about 

 35,000 miles, first increasing in brightness, then fading away; in 5 minutes 

 they had vanished. They did not alter the shape of a group of large black 

 spots which lay directly in their paths. Momentary as this remarkable phe- 

 nomenon was, it was fortunately witnessed and confirmed, as to one of the 

 bright lights, by another observer, Mr. Hodgson at Highgate, who by a 

 happy coincidence had also his telescope directed to the great luminary at 

 the same instant. It may be, therefore, that these two gentlemen have 



